Energy-storage company LightSail Energy has raised $37.3 million in Series D funding, led by investor Peter Thiel. Khosla Ventures, which incubated the company and led LightSail's earlier rounds; Bill Gates; Innovacorp; and several other investors also participated in the round.

Founded in 2009, LightSail Energy applies thermodynamics to solve the problems of today's electrical grid. For instance, the lack of economical energy storage on a megawatt scale has limited the penetration of renewable energy, such as wind and solar, in many parts of the world, and has limited transmission grid capacity.

LightSail says its technology makes power available when it’s needed, not just when it’s available, as well as helps to manage the increasing demand for peak power, thus making the entire grid more reliable and more practical for erratic renewable sources of energy.

“This investment round will enable LightSail to bring its first grid-scale energy-storage products to market,” says Steve Crane, co-founder and CEO of LightSail Energy. “With the support of a truly extraordinary group of investors, LightSail is well positioned to tackle, once and for all, a problem that’s bedeviled the electrical industry for more than a century. We want to democratize energy - to enable renewable sources to supply energy on demand locally and at a lower cost than centralized fossil-fuel based generation.”